Pipe line treating system



June 15, 1937. w. WOELFLIN PIPE LINE TREATING SYSTEM Filed Aug. 8, 1952 2 Sheets-Sheet l June 15, 1937, w. WOELFLIN 2,083,800

V PIPE LINE TREATING SYSTEM Filed Aug. 8, 1952 2 Sheets-Sheet 2 4 x Z5 a 1 i 39 gram, MIMA&\\

ATTORNEK Patented June 15, 1937 UNITED STATES PATENT OFFICE PIPE LINE TREATING SYSTEM Application August 8, 1932, Serial No. 827,910

23 Claims.

My inventionrelates to the electric dehydration of petroleum emulsions, and more particularly to a novel treater which finds particular utility in this art, though certain of the features of this treater are not limited thereto.

It is often necessary to transport petroleum through pipe lines for considerable distances by pumping from one temporary storage to another storage, and it is an important object of the present invention to provide a pipe-line treater which is connected in such a pipe line so that the emulsion flowing through the-pipe line is electrically treated before being discharged into a more remote section of the pipe line or into a storage or settling means. Such a treater can be of relatively small dimensions and need not necessarily include a cent thereto.

It is a further object of the invention to utilize a pipe line carrying petroleum which may be in the form of an emulsion. If no separating means is provided at each treater, each treater will merely agglomerate the water particles of such an emulsion into somewhat larger masses. Several advantages thus accrue. Not only is the treatment effected in steps, but with certain gasblown emulsions the particle-size can be progressively increased by successive treatments, and there will be less tendency for an extremely tight emulsion to be formed due to the agitation caused by turbulent flow in the pipe.' Such treaters spaced along a pipe line will insure that the water particles will be of larger size than would otherwise be the case. This structure is also advantageous in that it delivers to the treater adjacent the settling means an emulsion composed of larger water particles suspended in a continuous phase of oil, this emulsion being relaatively easy to treat to effect the final agglomeraalternative form of the invention.

tion preparatory to separation. Such a system alsopermits higher velocities through a-pipe line inasmuch as it controls the re-emulsifying tendency caused by agitation in the pipe and decreases the viscosity of the fluid.

It is a further object of the invention to position such a pipe-line treater in the pipe line and preferably below the surface of the ground, thus eliminating piping and being especially valuable in colder climates where operating dimculty is experienced at extremely low temperatures.

Further objects of the invention lie in the construction of the treater, and especially in utilizing a pipe or a section of the pipe line itself as an separating means adjaelectrode, and providing a central electrode extending therein from an adjacent chamber.

The simplified construction is another feature of the invention, the preferred embodiment ber opening thereon and in which the insulator is positioned.

It is a further object of the invention to remove the back pressure on such a treater to such an extent that gas is liberated from the emulsion undergoing treatment and enters the space around the insulator.

A further object of the invention is to direct the incoming emulsion centrally into the length of pipe forming the outer electrode and toward the inner electrode, and, in some instances, to supply a dielectric oil to the space around the nozzle and inside the outer electrode.

Another and very' important object of the invention is to provide a method and apparatus for protecting an insulator by flowing a stream of dielectric material along the surface thereof -to prevent accumulation of conducting material tion will be made evident hereinafter.

Referring to the drawings- Fig. 1 is a view partially in section illustrating two pipe-line treaters installed in position along a pipe line.

Fig. 2 is a vertical sectional view of the preferred embodiment of the treater.

Fig. 3 is asectional view taken on the line 3-4 of Fig. 2 and illustrates the insulator protecting system.

Fig. 4 is an elevational view illustrating an Referring first to the details of the preferred embodiment of the invention best shown in Fig. 2, this treater includes a container or an enclosing structure III which may conveniently, though not necessarily, include an intake T H, a length of pipe l2, a discharge T IS, a reduction nipple I4, and a connecting nipple l5.

The incoming emulsion flows through an intake section of pipe 18 which forms a part of a pipe line Hi, this intake section of pipe extending through a head 20 closing one end of the intake T II. A nozzle 2| is secured or formed on the inner end of the intake pipe l8 and cooperates therewith in defining a nozzle structure 22. This nozzle structure extends substantially through the intake T II and past an opening formed in a leg 24 of this T. The incoming emulsion is thus directed centrally into the length of pipe I2 due to the action of the nozzle structure 22. The discharge end of this length of pipe I2 provides a flange 26 which is secured to the discharge T I3 as shown. A discharge chamber 21 is formed inside the main body of the discharge T I3, this T also providing a leg 28 which preferably extends upward from the discharge chamber 21 and provides an insulator chamber 29 therein,

the discharge chamber and the insulator chamber cooperating in defining an enlarged chamber communicating with the interior of the length of pipe I2. If desired a nipple 30 can be secured to the upper end of the leg 28 so as to enlarge the insulator chamber 29 to correspond to the particular insulator utilized.

In Fig. 2 I have shown an insulator 32 mounted in a plate 33 closing the upper end of the insulator chamber 29, the insulator extending downward in this chamber but terminating near the boundary of the discharge chamber 21. The insulator chamber may contain a liquid carrying conducting particles (e. g. such as the emulsion constituents), this liquid contacting the surface of the insulator 32, or this insulator chamber may contain a gas as will be hereinafter set forth. While it is possible for the inner portion of this insulator to extend downward into the discharge chamber 21, it is desirable that the inner end thereof terminate short of the central portion of the discharge chamber so that this inner end of the insulator will not seriously interfere with the flow taking place through this discharge chamber.

Extending completely through the insulator 32 is a conductor means in the form of a rod 35 which carries a pair of supporting arms 36 at the lower end thereof, these supporting arms being bent downward to extend into the discharge chamber as shown. Suitably secured to the lowermost ends of these arms is a rod electrode 38 which extends from the discharge chamber2'linto the length of pipe I2 which forms the outer electrode and terminates in a relatively sharp point 39 which is in axial alignment with and which terminates short of the nozzle 2I so as to pierce the stream of emulsion delivered from the nozzle 2|. The annular space between the'rod electrode 38 and the outer electrode formed by the length of pipe I2 thus comprises a treating space 40 in which an electric field may be set up from a source such as a transformer I providing a sec-' ondary winding 42 connected between the conductor 35 and the length of pipe I2.

In the preferred embodiment I prefer to utilize a dry oil pipe 48 communicating through a valve 49 withv the interior of the leg 24 of the intake,

T II. A dielectric liquid is delivered to this pipe from any suitable source and thus enters the annular space between the body of the T II and the nozzle structure 22, this space being indicated j charge chamber 21.

into the annular treating space 40, or as the constituents are moving therethrough.

Difliculty is sometimes experienced with insulators of this type when such insulators have access to a conducting material. The water in the emulsion forms such a conducting material, and a coating or deposit of this material often accumulates on the surface of the inner portion of the insulator through condensation of vapors, or by a mixture of the oil and water being sprayed on the insulator, or by positioning the insulator surface in a liquid carrying conducting particles. Such a coating of conducting material tends to form a conducting path along the surface of the insulator and to cause an arc-over which develops sufiicient heat to break the insulator. In the present invention I have developed a system and method for successively perventing such insulator break-downs. In the preferred embodiment a pipe 55 extends from the dry oil pipe 48 and' into the insulator chamber 29, the flow of dry oil being controlled by a valve 56. Any suitable distributing or spray means may be utilized for directing the dry oil along the sur-- face of the insulator in such a manner as to cover this surface with a flowing stream of the dielectric oil which tends to wash the surface of the insulator and remove conducting particles.

In the preferred embodiment I utilize an annular spray ring 58 provided with a number of downward directed openings or small jets 59 disposed adjacent the surface of the insulator and directing streams of the dry oil into contact therewith, these streams cooperating in forming an envelope which surrounds the insulator and flows downward therealong. These openings comprise an orifice means, though it should be understood that other types of orifice means can be utilized, such as arcuate slots, separate nozzle means, etc., all of such means being'included in the term orifice means. In some instances, however, it is not necessary to use this insulator-protecting device, in which case the valve 56 can be closed. In other instances periodic use of this flow of oil along the surface of the insulator is sufficient to prevent break-down thereof.

It is also possible to so operate the treater that the upper end of the discharge chamber 21 and the insulator chamber 29 are substantially filled with a gas, this gas having suiiicient dielectric properties to protect the insulator. In the preferred embodiment this can be accomplished by reducing the back pressure on the treater to such an extent that gas is liberated from the emulsion and moves upward to fill the insulator chamber 29 and the upper portion of the dis- When thus operated, the surface of the treated emulsion lies approximately as indicated by the dotted lines SI of Fig. 2.

This condition may be easily attained by utilizing some means of reducing the pressure in the discharge chamber 21 to such a value that the gas will be liberated. In Fig. 1 I have illustrated two methods of accomplishing this end, namely, by the utilization of either a pump or a column of liquid flowing from the discharge chamber which lowers the pressure therein. The combination including a pump is shown in the left half of Fig. 1, the pump being indicated by the numeral III and intaking from a pipe 'II communicating with the connection nipple I and discharging into a section of pipe I2 which may either extend directly to a settling tank to effect a separation of the constituents or may form a part of the pipe line I9.

The treater shown in this portion of Fig. l is substantially the same as that shown in Fig. 2, corresponding numbers indicating corresponding parts. The unit is preferably mounted in alignment with the pipe line it and is preferably positioned in a pit i3 formed below the surface of the ground and lined with concrete. A cover it preferably extends over the top and carries an insulator i5 through which the supply leads for the transformer ti extend. These supply leads are also electrically connected, as by conductors it, to a motor ii which drives the pump it. If a circulation of dry oil is utilized this may be derived from any suitable source not shown, flowing through the pipe 48 previously described, this pipe extending through the cover id. This positioning of the treater is especially advantageous in cold climates, and, if desired, the interior of the pit may be heated or heat-insulating means voil. This value is not, however, invariable and may be utilized on the cover i i. As many of these treating units as desired may be installed along the pipe line, as previously described, each unit not only compensating for the emulsification which takes place in the pipe line due to pipe friction, but also agglomerating .the' water particles into progressively larger droplets so that when the emulsion is moved into the last treater preparatory to separation a quick treatment and subsequent separation will be efiected.

Another way in which thetreater can be very advantageously utilized is shown inthe right halt of Fig. 1 wherein the treater is mounted above the uppermost portion of a separating tank 32 including a water outlet B3 and a dry oil outlet at. Brackets 85 may be utilized for mounting the treating unit above the uppermost portion of the tank, and a discharge pipe tt may communicate with the discharge chamber 2i;

present in the downward extending portion of the pipe ddwhich will reduce the pressure in the discharge chamber 2i so as to allow the liberation of the gas as previously set forth, this column of treated emulsion taking the place of the pump it.

In this connection a portion of the dry oil flowing through the pipe M is conducted to storage or to an additional pipeline through a pipe E39.- j A small portion of the dry oil is withdrawn" through a pipe til by a pump at driven by a motor 92. This pump circulates the dry oil through a pipe 98 corresponding to the pipe 33 previously described, a portion of this oil flowing -'into the treating spacealong with the incoming emulsion, and another portion, if desired, flowing around the insulator through the pipe 55.

It will be understood that it is notin all events necessary to utilize dry oil either for the purpose of protecting the insulator or for moving through the electric field along with the emulsion. Many emulsions can be very successfully treated without the use of such a liquid dielectric. Usually with emulsions having more than approximately 12% water it is desirable to circulate the dry depends both upon the size of the treater and other factors of operation.

As a practical example of the operation of such a treater, the length of pipe l2 comprising an outer electrode may be formed of a piece of 3" pipe and the rod electrode 28 may be from it" to 1" in diameter. A nozzle having an orifice of approximately in diameter gives very" satisfactory treatment, and with such a treater anaverage potential gradient of'13,000 volts per inch across the gap will be very satisfactory, the cuts ranging in the neighborhood of 1.6% or less. Usually more satisfactory treatment will be obtained by the use of small rod electrodes. The pressure on the incoming emulsion is not critical, pressures from 35 lbs. per sq. in. to 200 lbs. per sq. in. giving very satisfactory treatment. It should be understood, however, that these values are only illustrative and that I am not in any way limited thereto.

It is sometimes desirable to preliminarily mix the dry oil and the emulsion before entry into the pipe i2. This may conveniently be done in the form of the invention shown in Fig. 4 in which a T 96 is connected both to the pipe line i9 and to the dry oil pipe 58, the relative amounts of dry and wet oil being proportioned by the setting of a valve 96 utilized in the pipe dd. A mixer 97 may be utilized, if desired, for more intimately mixing the dry oil and the emulsion. Such a mixer may be-of the mechanical agitation type or may comprise a conventional mixing valve or other well-known type of mixing apparatus. The

mixture then moves through the inlet pipe it.

andthe nozzle 26 as previously set forth.

While I have not shown a heating means for heating the incoming emulsion, it will be clear that such heating means may be used as in conventional practice.

One of the features .of the present invention lies in the use of a small rod electrode which extends into a pipe forming a central section of a pipe line so that the pipe itself is used as an electrode. This results in a simplified structure and one which is found to be very effective in the treatment of petroleum emulsions especially when utilized in conjunction with a pipe-line treater.

,Another feature of the invention is the mounting of such a small rod electrode in a chamber adjacent one end of the pipe which forms the outer electrode. This permits the mounting of the rod electrode to be spaced from the main -treating space so that no supporting means restricts the flow through the space between the electrodes. v

The particular mode of fong the concentric streams of oil and emulsion is also a feature of thepresent invention, as well as the mode of operation wherein the insulator is surrounded' by the gas liberated from the emulsion. The insulator protecting system including the utilization of a flow of dry oil along the surface of the insulator is also a very important feature, as is also the positioning of the insulator in a chamber to one side of the main discharge chamber so that it does not interfere with the main flow oi emulsion.

a I claim as my invention:

i.- In a pipe-line treater, the combination of: a horizontally disposed pipe comprising an outer electrode connected to the pipe line; walls connected to one end of said pipe and forming an enlarged chamber into which said pipe discharges; a horizontal rod electrode extending from said enlarged chamber into said pipe and wis in said enlarged chamber toward said rod electrode for mounting said rod electrode to extend centrally into said pipe; nozzle means extending into the oppositeend of said pipe from said walls forming said enlarged chamber and directed toward but spaced from the inner end of said rod electrode; means for supplying the emulsion to be treated to said nozzle means, said emulsion being thus discharged from said nozzle and moving through said pipe and thence into and through said treating space and being thereafter discharged into said enlarged chamber, the inner end of said insulator means terminating short of the main stream of emulsion discharged from said nozzle; and means for impressing a potential difference between said rod and said outer electrode.

2. In a pipe-line treater, the combination of: a length of pipe connected to a pipe line and comprising an outer electrode; a nozzle connected to said pipe line and of smaller diameter than said length of pipe and extending into one end thereof to define an annular space therebetween; a rod electrode extending into the other end of said length of pipe and toward said nozzle but terminating a distance therefrom, said rod electrode cooperating with said length 01' pipe in defining an annular treating space; insulator means supporting said rod electrode in said length of pipe and spaced from the liquid stream discharged from said nozzle; means for establishing a potential difierence between said rod electrode and said length of pipe; means for supplying the emulsion to be treated to said nozzle; and pipe means communicating with said annular space between said nozzle and said length of pipe for supplying a liquid theretodissimilar'to said emulsion said liquid flowing from said annular space around the stream of said emulsion discharged from said nozzle whereby said liquid and said emulsion move through said treating space and are discharged from said length of Pipe.

3. In an electric treater, the combination of:

an outer electrode; walls attached to one end of.

said outer electrode and forming a discharge chamber into which moves the liquid flowing from said outer electrode; walls forming an insulator chamber at one side of said discharge chamber; an insulator in said insulator chamber and extending toward but terminating short of the central portion of said discharge chamber to be substantially removed from the main body of liquid flowing through said discharge chamber; a rod electrode retained by said insulator and extending into said outer electrode; and means for impressing a potential diilference between said rod electrode and said outer electrode.

4. In a pipe-line treater, the combination of: a length of pipe; a pipe T secured to the dise charge end of said lengthof pipe and providing a discharge chamber and an insulator chamber; an insulator mounted to extend into said insulator chamber; a rod electrode retained by said insulator and extending into said length of pipe; means for establishing an electric field between said rod electrode and said length of pipe; and means for supplying the emulsion to be treated to said length of pipe, the treated emul sion moving through said T.

5. In a pipe-line treater, the combustion of: a length of pipe; a pipe T secured to one'end of said length of pipe and providing a discharge chamber and an insulator chamber; an insulator mounted to extend into said insulator chamber; a

rod electrode retained by said insulator and extending into said length of pipe; means for establishing an electric field between said rod electrodef and said length of pipe; an intake T secured to the other end of said length of pipe and providing a leg; a nozzle extending into said intake T to define an annular space communicating with said leg; means for supplying a dielectric oil to said leg and hence into said annular space; and means for supplying the emulsion to be treated to said nozzle.

6. A combination as defined in claim 5 in which said nozzle extends to a position beyond said leg to direct a central stream of emulsion into said length of pipe.

7. A method of protecting an insulator of an electric dehydrator which extends into a gasfilled space communicating with a conducting medium, which method is characterized by the step of washing the surface of said insulator in said gas-filled space by flowing a dielectric liquid along said surface.

8. A method of protecting an insulator extending into a liquid in a dehydrator which liquid carries conducting particles, which method includes the step of continuously introducing into said liquid and at a section adjacent the surface of said insulator an annular stream of dielectric liquid flowing longitudinally along and in contact with the surface of said insulator.

9. In a pipe-line treater, the combination of: a pair of electrodes defining a treating space; walls forming a discharge space into which flows the treated liquid discharged from one end of said treating space; walls defining an insulator chamber communicating with' said discharge space and positioned thereabove; an insulator extending downward in said insulator chamber and mounting one of said electrodes; means for delivering the emulsion to be treated to said treating space, said emulsion being treated therein and flowing into said discharge chamber and said emulsion including a conducting medium tending to accumulate on the'surface of said insulator; means for flowing a stream of dielectric oil along the surface of said insulator to pro-.

being of sufllcient intensity to coalesce the dispersed droplets of the dispersed phase of said emulsion, this dispersed phase remaining associated with the continuous phase of said emulsion during successive subjection of said emulsion to said fields, at least partial re-emulsiflcation of said emulsion constituents taking place during their flow between said spaced sections to form .a modified emulsion of different character from that discharged from the next preceding electric field but not re-emulsified to the degree of the emulsion entering the preceding field whereby said emulsion is successively treated.

11. A method-of treating an emulsion flowing along a pipe line, -which method includes the steps-of: establishing a plurality of electric fields positioned at spaced sections along said pipe line and through which the, emulsion. constituents successively pass, each of said fields being of sufficient intensity to coalesce the dispersed droplets into larger masses, at least partial re-emulsification 'of said emulsion constituents taking insulating said electrode means from said length of pipe; means associated with said electrode means for establishing an electric field insaid pipe 01' sufilcient intensity to exert a coalescing action on the dispersed particles of said emulsion;

treated emulsion discharged from said length of pipe before substantial separation has been effected whereby said second section of pipe receives the same emulsion constituents as passed which said insulator chamber extends upward from said-longitudinal passage, and including low-back-pressure withdrawal means communieating with that end of said passage from which place during their flow between said spaced secthrough said intake section of pipe and tends to tions to form a modified emulsion of different re-emulsify the treated emulsion constituents; an character from that discharged from the next electric treater communicating with said second preceding electric field but not re-emulsified to section of pipe and receiving the emulsion conthe degree of the emulsion entering the preceding stituents flowing through said second section of field whereby said emulsion is successively treatpipe in a condition wherein these emulsion con- 10 ed until the size of said dispersed droplets become stituents are at least partially re-emulsified due great enough that these droplets will separate to the friction in said second section of pipe, when the emulsion constituents are allowed to .said electric treater including means for estabisettle; introducing the emulsion constituents dislishing an electric field to which said emulsion charged from the last electric field into a settling constituents are subjected said field coalescing lit space; and separately removing the separated the dispersed particles thereof; and separating constituents from said settling space. means receiving the emulsion from said electric 12. A method of treating an emulsion flowing field in said electric treater for separating the along a pipe line, which method includes the emulsion constituents.

steps of establishing a plurality of electric fields 16. In an electric dehydrator for emulsions .20

positioned at spaced sections along said pipe line adapted for use in conjunction with a pipe line and through which the emulsion constituents formed of a plurality of sections, the combination successively pass, each of said fields being of of an enclosing structure open at its ends to suificient intensity to coalesce the dispersed drop-. receive emulsion from one section of said pipe lets into larger masses; adding to the emulsion line and discharge treated emulsion into an- 5 constituents at sections spaced along said pipe other section of said pipe line; a rod electrode line a dielectric liquid whereby a succeeding field in said enclosing structure and extending paraltreats the emulsion constituents treated by the lel to the direction of flow of said emulsion preceding fields together with the added dielecthrough saidenclosing structure and being surtric liquid; and separating said emulsion conrounded by the stream of emulsion moving stituents after subjection to the last electric through said enclosing structure; a supporting field. arm holding said rod electrodein position and 13. A method oi" dehydrating an emulsion by extending transverse to the direction of flow of the use of an electric treater having-an insulator said emulsion through said enclosing structure;

5 chamber in the upper end thereof, which method insulator means extending through d e c S- includes the steps of: moving a stream of the ing structure and providing an electric conducemulsion into said treater; establishing an elector electrically connected to said rod electrode tric field in said treater of sumcient intensity r 0 for conducting a high potential current therecoalesce the 'dispersed droplets of said emulsion to; and potential-supply means connected to said into larger masses; and forcibly withdrawing the enclosing structure and to said conductor for es- 40 emulsion constituents from said treater before tablishing an electric field in the space inside said substantial separation thereof has taken place enclosing structure and around said rod elecand at such rate that the pressure in said treater trode to electrically treat, the emulsion fiowing is maintained sufiiciently low to liberate gas h ou Sp around Said d e rodefrom said emulsion in said treater, said gas ris- 1'7. In an electric treater for emulsions for use ingto said insulator chamber. in conjunction with a section of pipe through 14. A method of dehydrating an emulsion by which a stream of emulsion flows: walls forming the use of an electric treater having an insulator a longitudinal passage communicating at one end chamber in the upper end thereof, which method with said section of pipe whereby said emulsion includes the steps of: moving a stream of the flows through said longitudinal passage in a emulsion into said treater; establishing an elecstream which substantially fills said longituditric field in ,said treater of sufilcient intensity to nal passage; walls forming an insulator chamcoalesce the dispersed droplets of said emulsion her to one side of said longitudinal passage cominto larger masses; forcibly withdrawing the municating therewith but substantially removed emulsion constituents from said treater before from the main portion of said stream of emulsubstantial separation thereof has taken place sion; an electrode in said passage and in the path and at such rate that gas is liberated from said of travel of said stream of emulsion to be sur-'- emulsion in said treater and rises .to said insurounded thereby; an insulator in said insulator lator chamber; and withdrawing with said emulchamber and supporting said electrode; and sion constituents any excess gas liberated in said means for establishing an electric field in said 0 treater over and above the quantity of gas necesp ss adj t d electrode. sary to fill saidinsulator chamber. 18. A combination as defined in claim 1'? in 15. In combination in an emulsion-treating which said insulatorrterminates adjacent the insystem: an intake'section of pipe through which nerend of said insulator chamber and thus termiflows the emulsion to be treated; a length of pipe nates short of said main portion of said stream, 5 communicating with said intake section of pipe and including anarm. supported by said insulator to receive the emulsion flowing therethrough; and attached to said electrode and extending electrode means centrally disposed in said length transversely into said stream of emulsion flowof pipe and extending axially therein; means for ing through said longitudinal passage.

19. A combination as defined in claim 1'? in 76 a second section of pipe receiving the electrically said stream of emulsion moves permit gas to be liberated from said emulsion and rise in said insulator chamber to surround said insulator.

20. In an; electric treater for emulsions, the combination of: a container containing the emulsion to be treated; electrode means in said container for setting up an electric field therein; an insulator in one portion of said container and associated with said electrode means; orifice means around said insulator and discharging inside said container for flowing an envelope of liquid along the surface of said insulator in washing relationship therewith; and means for supplying to said annular means a liquid of higher dielectric strength than the emulsion whereby the surface of said insulator is washed with said liquid of higher dielectric strength to prevent accumulation thereon of the emulsion constituents.

21. In an electric treater for emulsions, the combination of: electrode means defining a treating space containing said emulsion; walls forming an insulator chamber communicating with said treating space but spacedtherefrom; an insulator bushing extending through one of said walls and providing a conductor electrically connected to said electrode means; annular means in said insulator chamber around said insulating bushing and providing orifice means directing an envelopeof liquid along said bushing in surrounding relationship therewith; and

7 face of an insulator extending into an electric treater, which method includes the steps of: introducing into said treater an emulsion of such character that it would tend to cause electric failure of said insulator it the emulsion constituents are brought into contact with said exposed surface; and washing said exposed surface of said insulator by flowing a thin moving envelope of dielectric liquid along said exposed surface to separate said exposed surface from any of said emulsion constituents in said electric treater.

23. A method of treating an emulsion flowing along a pipe line, which method includes the steps of: establishing a plurality of electric fields positoned at spaced sections along said pipe line, each of said fields being of sufllcient intensity to coalesce the dispersed droplets of said emulsion into larger masses; moving the emulsion constituents successively through said fields without substantial separation of the treated constituents from each other during passage between said fields; and separating the emulsion constituents from each other after subjection to the last electric field.

WILLIAM WOELFLIN. 

